Clutch lever operation stiff and very noisy the type of noise you would relate to something seizing up. Since this started the neutral warning light has stopped coming on.

what is stiff (add a noun here)
blush.....
clutch pedal stiff
shifter lever stiff.
grinds , a bad clutch will make the lever seem stiff or will grind, if forced.
gears balk? same as stiff.
false neutrals. (slips , gear not engaging)

Check your clutch pushrod is clean and can move freely when operated. Otherwise it sounds like the clutch internals.

1. Clutch Lever
   • As the clutch lever is operated over time, it gradually loses its grip on the clutch cable, weakening the clutch lever action until it barely moves the clutch plates. Maintain the clutch lever by ensuring the free play at the lever meets the specifications of the motorcycle's user manual, in which you will also find instructions on how to make this adjustment.
     
   Clutch Cable
   • Unlike the gradual onset of a clutch lever problem, the somewhat uncommon failure of a clutch cable is instantaneous. With little warning, the clutch lever goes completely slack and the clutch will be inoperable. Keeping a clutch cable well lubricated can prevent failure. However, in the event of a cable failure, a registered dealer should fit a replacement.
     
   • 
     
   Clutch Plates
   • Problems with the clutch mechanism itself normally manifest themselves in the gear change rather than in the applying and releasing of the clutch lever. Noise, chattering or slipping can be the result of misaligned or warped plates, leaks in hydraulic cables or bearings. Although more serious, if recognized early, these problems will be relatively inexpensive to repair.
     

Instructions

1. • 1 The gears on a motorcycle run in this order: first, neutral, second, third, fourth and fifth. When you are moving, shifting up from first gear will skip over neutral and shift you right into second gear. The only time that shifting up from first will get you into neutral is when you are not moving.
     
   • 2 Pull in the clutch lever and tap the gear lever down until it stops. This will signify first gear. Pressing the gear lever down will shift you down one step and pressing it up will shift up one step.
     
   • 3 Tap the gear lever up one click while still holding in the clutch. This will put the bike into neutral.
     
   • 4 Start the bike. The bike needs to be in neutral to start.
     
   • 5 Hold in the clutch lever and tap the shifting lever down to shift to first gear.
     
   • 6 Release the clutch slowly and give it just enough gas to get moving.
     
   • 7 Listen to the motor to know when you need to shift. If the engine is making a low grumbling noise, then it will need to be shifted down. If it is making a high squealing noise, then it needs to be shifted up.
     

Instructions

1

The gears on a motorcycle run in this order: first, neutral, second, third, fourth and fifth. When you are moving, shifting up from first gear will skip over neutral and shift you right into second gear. The only time that shifting up from first will get you into neutral is when you are not moving.
2

Pull in the clutch lever and tap the gear lever down until it stops. This will signify first gear. Pressing the gear lever down will shift you down one step and pressing it up will shift up one step.

3

Tap the gear lever up one click while still holding in the clutch. This will put the bike into neutral.
4

Start the bike. The bike needs to be in neutral to start.
5

Hold in the clutch lever and tap the shifting lever down to shift to first gear.
6

Release the clutch slowly and give it just enough gas to get moving.
7

Listen to the motor to know when you need to shift. If the engine is making a low grumbling noise, then it will need to be shifted down. If it is making a high squealing noise, then it needs to be shifted up.

Possible stuck brake or seized motor or jammed brake lever.

Is the clutch lever sized or is the plates sized?
Usually the plates inside sizes, all you have to do is select gear 2 or 3 without starting the bike's engine,operate the clutch lever and push the bike,it should release, the rear wheel should now rotate freely with clutch lever in operation and in gear.
Hope this helps!